Paints and stains are often used to protect and/or decorate a surface. Stains are transparent or semitransparent solutions or suspensions of coloring agents (such as, for example, dyes or pigments and the like) in a vehicle, and typically are designed to color a surface without hiding it or leaving a continuous film. As a result, the stained substrate (typically a species of wood) is colored, but the grain pattern is generally not hidden. In contrast, paints are usually opaque solutions or suspensions of coloring matter in a carrier, designed to hide or cover a surface with an opaque film.
Computerized color matching techniques using spectrophotometers are used with paints. However, the use of computerized color matching techniques with transparent or semitransparent stains has not been successful, due to the transparent or semitransparent nature of stains, the wide variety of available substrates (e.g., wood species, each of which imparts its own contribution to the color), and the variations of color within even a single substrate sample.
Instead, transparent or semitransparent stains are conventionally color matched, if at all, using a trial-by-error method. In one such trial-by-error method, a colorist inspects the color of the stain standard and then guesses regarding the pigments and relative concentrations of same necessary to provide a color matching stain. A stain is then prepared based on the pigment and concentration guesses. The stain is applied to a substrate and then the stained substrate is compared to the stain standard. If the visual inspection indicates that the stain standard and the stained substrate do not match, the colorist guesses at the amount of pigments to add to the stain and the new stain is applied to the substrate. These steps are repeated until the colorist determines that there is a color match. As can be appreciated, such a trial-by-error method is tedious and relies upon the skill of the colorist for its effectiveness.
The aforementioned method is not at all practical for do-it-yourselfers, mass merchants or home center staffs. Instead, the customer is usually required to select the closest “color” from a very limited palette of pre-mixed stains. For example, color matching may be conducted by comparing a stained article (target) to a limited number of colored samples, usually between about 15 and about 20, on a display rack having a very limited selection of substrates. The limited choices are often not close enough for good color matching; resulting in a very unsatisfactory experience for many customers. Moreover, the differences in the base color (background) of different substrates (e.g., wood species) make it difficult to obtain good matching of a color of the stain on different substrates or types of wood.
Accordingly, there is a need in the art for an improved method of color matching transparent or semitransparent stains and an apparatus that can select, suggest, and/or prepare an accurate color match for stains for different substrates, e.g., different wood species. The present invention is directed to such a method and apparatus.